Preheat oven to 425 degrees with a pizza stone placed on the lowest rack.

Heat oil in a large skillet over medium-high. Add turkey and cook, stirring to crumble, until lightly browned, about 4 to 5 minutes. Stir in bell pepper, onion, cumin, chili powder and garlic - season with salt and pepper. Cook until the vegetables are just crisp-tender, about 4 to 5 minutes. Add salsa verde, remove from the heat and stir to combine.

Sprinkle enough cornmeal to lightly cover a pizza peel. Divide dough into 4 equal pieces. On a lightly floured surface, stretch each piece of dough into a rough 6" x 4" rectangle. Evenly divide the turkey mixture between one side of each dough rectangle. Divide the cheese between the tops of each - fold dough over turkey mixture and press edges together to seal. Drizzle a little olive oil over each calzone and rub in.

Carefully transfer calzones to the pizza peel and slide onto the stone - bake until golden brown, about 12 to 15 minutes. Remove and let cool slightly. Serve each calzone with a dollop or two of sour cream.